Many electrical connectors are known which provide electrical connection between contact surfaces of a daughter board and contact areas of a mother board. In general, the connector has contacts positioned therein which extend from a first mating surface of the connector to a second mating surface. The contacts have posts which extend from the connector and make electrical engagement with the contact areas of the mother board. The daughter board is then inserted into the connector and rotated to its operating position. As this rotation occurs, contact projections of the contacts engage the contact surfaces of the daughter board. In order for this electrical engagement to be maintained, it is essential that latch arms be provided to cooperate and maintain the daughter board in the operational position.
An example of this type of electrical connector is described in U.S. Pat. No. 4,737,120. As is shown in FIG. 1 of that patent, the latch members are provided at the ends of the connector, and are integrally molded with the housing. The configuration of the latch members provides the latch members with the resilient characteristics required in order to allow the latch members to cooperate with the daughter board to maintain the daughter board in electrical engagement with the terminals of the connector.
However, several problems are associated with the configuration of the latch member described above. As the latch members are molded from plastic material, and as the resilient characteristics of plastic is not significant, the latch members are likely to take a permanent set, particularly when the connector is used over many cycles. This likelihood is increased due to the fact that the latch members must have a relatively thin width when molded. This requirement reduces the durability of the latch members, so that the latch members are only strong enough to support approximately 25 cycles (insertions and removals of the printed circuit board). Consequently, if the electrical connector is to be used over many cycles, the risk of failure of the electrical connector is greatly increased.
It is also important to note that a relatively small displacement of the molded latch is enough to cause the latch to take a permanent set Consequently, as the daughter board can vary in size, and still fall within the tolerance limits for the connector, it is possible that a relatively large board will be inserted into the slots, and then be followed by a relatively small board. The insertion of the large board into the slot can cause the plastic latch to take a permanent set, so that as the small board is inserted, the latch will not be effective in maintaining the board in the slot, resulting in an ineffective connector.
It would therefore be advantageous if the latch members could be made from a material having the desired resilient characteristics. This requires the latch members to be separately manufactured and inserted into the housing after the housing has been molded.
Another problem associated with the connector disclosed in U.S. Pat. No. 4,737,120, and other similar connectors, relates to the mounting posts. Generally, mounting posts cooperate with openings in the mother board to position and maintain the connector and terminals in place until soldering or the like occurs. However, it is important to note, that the dimensions of the posts must be minimized, as the space available on printed circuit boards is at a premium. Consequently, the width of the posts must be held to a minimum in order for the connector to occupy a minimal amount of board real estate. This miniaturization of the post causes the post to be relatively weak, particularly because the post is manufactured from molded plastic. Therefore, as the post is relatively weak, it is possible that damage will occur to the post during the shipping of the connector, thereby resulting in an ineffective connector.
It would therefore be advantageous if the post could be strengthened without the need to increase the area which the post occupies. The utilization of this type of post would require the post to be attached to the connector in some manner, as the post would no longer be able to be molded at the same time as the housing of the connector.